Installing Weber 34ADF on '79 2L -- Questions

[RJ80]

So I just purchased a new 34ADF carb for my '79 2L car and can't wait to get that old ADHA off! I've been reading over related threads but can't find the answer to a couple questions.

I'll be using an 1800 single-plane intake manifold. Would a standard 2L intake manifold gasket work or do I need a specific 1800 gasket? If they are the same, should I reuse the old if it appears to be in good shape, or buy a new one (I'm guessing the latter). I also wasn't supplied with a new carb-to-manifold gasket. Would the carb spacer gaskets that IAP sells do the trick?

I've got a feeling I'll have more questions when I'm actually installing the thing, but from what I've read, the installation should be pretty straightforward.

Thanks in advance...

[mbouse]

2L intake manifold gasket will work for an 1800 intake, given that the 2L will be larger on the front end. the extra length is for the EGR port that is fed from the exhaust side. for the pittance of additional expense, why not go with a new 1800 gasket? the #1 thing here is to be sure you prevent coolant leaks, and #2 to prevent vacuum leaks.

i ran for two years with a home made cork gasket under my 32/36 Weber after removing the sickly 28/32. i recently modified that with IAP's 12mm carburetor spacer, which came with two gaskets. the purpose of this gasket is to prevent vacuum leaks between the two metal surfaces. it does not need to be an elaborate material, but make sure it does not interfere with the butterflies or fuel mixture distribution. you can get appropriate gasket material at just about any parts store; cutting it to size takes a little patience.

[RJ80]

Thanks for the quick response, Mike.

Been doing some more reading and it appears removing the intake manifold is quite the job. My original intention was to keep the original carb/manifold/smog equip. together and reinstall for CA smog tests every two years. It appears that the simplest solution in my case may be to just bolt up the new 34ADF to the stock dual plane manifold and keep all the smog equip. intact. I know the single-plane allows for more power (and a cleaner engine bay), but would I really be loosing a significant chunk of power to stay dual-plane? Is the 1800 intake conversion worth it if I have to reinstall the old every two years to pass smog?

[mbouse]

i do not pretend to know anything about passing emission testing, and do not advice folks who must do so. i did not realize you lived in such a location, or i would not have been the first to answer your questions.


be that as it may.... the difference in performance is SUBSTANTIAL

i've swapped intakes/carbs a couple of times in the past few years. after a time or two, even you could getter done in a day. but, i gotta admit that i'd look for a different alternative if i was faced with bi-annual inspections.

[So Cal Mark]

the smog issue gets a little complicated, only because of the differences in the egr systems. There are a couple of ways to approach it, but it involves either retrofitting the earlier egr system or swapping intakes every two years. You can get by using that carb as long as you have a stock air cleaner so that everything looks original. Your engine has the pulse air system, so the height of the air cleaner is also important to make everything hook up

[Daniel]

Hi RJ80


I did the ADF on the Dual Plane Manifold i haven't seen anyone else post any results on trying
this setup so i may be the black sheep on this issue . I have owned a few 1800s as well over the
years, after swapping Carbs on my 2L 79 Spider felt pretty much like a stock 1800 with the
single plane manifold to me . The power increase might have been about 10 HP or so .
IMO if you Replace that crappy carb with a Dual plane or Single Manifold either way the ADF is the real
difference as the larger Veturies flow that much more . As soon as you take her for a spin your going to feel
it in the seat of your pants . If you were building a bigger engine with large Cams and Carb replacing
the ADF i would not suggest this manifold at all as it would limit your flow but for a stocker or close to
stock it's fine .


Passing smog plumming was my issue as well and wanted it to look stock ! all the Links, Air filter,
lines fit right you just need to block off a few vacum lines and your done should take less then an
hour if you have experience working on cars . My Spider purrrrrrred like a kitten after i was done
to bad i didn't take photos to share maybe next time .

It would be great if you took some step by step photos along with a how the cars runs post them here
for the next guy who is interested in this upgrade it seems to pop up every few months .



Daniel

[RJ80]

The plot thickens! The earlier EGR system, Mark? I imagine sourcing a working system may be harder than the install... but what components might I need for this and how tricky to hook it all up? Might you have the parts? This sounds like something to seriously consider.

Daniel, I did come across your posts about using the dual-plane manifold. This may still be an option and I'd be more than happy to document the procedure should I go this route. Ideally, I would like to get as much power as possible since I already have the single-plane manifold here, but if the only viable option ends up being the manifold swap for smog, I'll seriously consider staying dual-plane.

[Daniel]

Hi RJ80

More power to you either way your going to be happy i was just pointing how i feel the power differnce
may end up being about the same with a dual or single plane manifold .
The 1800 Manifolds are much cleaner looking then the duals you get rid of a lot of vacum lines thats
as added bonus to going that route !


Daniel

[RJ80]

One more (silly) question... how do I tell if my ADF's vacuum advance port is... ported? I've located the port and it appears to be drilled in maybe a quarter of an inch... but there is no fitting coming out of it and still metal at the end of the passage. I'm not sure I see where it opens up to another passage anywhere inside.

EDIT: Yeah, just stuck a paperclip in there to see if there were any connections, and nope... just dead ends. Looks like I'll have to drill that out further and put a hose fitting in it

[racydave]

Ported means that basically you have no vaccume at idle with the choke off, and warm engine. Start the car and feel for suction, and raise the idle to see if it has vaccume at all. Ported will have vaccume above idle speed. Do not drill the carb!